Sum of n terms of a geometric series is
Sn = a1 (r^n-1)/(r-1)
a1 = 1st term = 4
r = common ratio = 12/4 = 3
so, the sum is
Sn = 4 (3^n-1)/(3-1) = 2(3^n-1)
Answer:
-46
Step-by-step explanation:
4-2(25)=
4-50=
-46
It helps to imagine the variable a sort of as a unit. Like with 5 minus 12 lemons, it has no bearings on the addition/subtraction here.
Factor out a and subtract.
I think I just had a stroke trying to read this